Dry cell and method of making the same



Jan. 13, 1931. G. w. HEISE DRY CELL AND METHOD OF MAKING THE SAME Filed Dec. 2, 19221 gwuento'o Patented Jan. 13, 19'3 1::

i j f f 71,788,320

' enemas w nnrsn, or MALVERNE,

COMPANY, INCORPORATED, A' cojr'r-Pem ricn 'orguuw K) 1 -DRY 'cnm. AND" METHOD nnit-rite" f Applicatic n filed December 2,1924; 'sriarnd.753,499.

order to preventthe cathode or bobbin electrode from disintegrating, particularly during the l assembly of the. several parts of the dry cell, it has beenicustomary, in manufacturing dry cells of these-called bag type,

to provide abobbin with awrapping ofbibulous material such as fabric or paper, -th'e wrapping being held in place about the bob bin by thread or. the like. Thismethod of wrapping the bobbin has either required a greatdeal of tedious handilabo'r or the. pros VlSlOII of more or less complicated andeX- penslve machines for accomphshmg the same cient in operation due to the fact that air bubbles have remained between the bibulous 'envel'ope and the bobbin or between the envelope and the gelatinized'paste commonly used in dry cells of this type.

Iii-order toeliminate air bubbles adjacent-to the wrapping it has been proposed to usepaper maintained in'close-fitting relation-to the bobbin by means of cereal paste, either applied to the paper before wrapping it about the bobbin or else'applied to the bobbin and-then wrapping the paper tightly about the same. r

The applicant has found" that the paper may be applied to the bobbin so as to: eliminate air bubbles without the use :of cereal paste and atthe same time the wrapperjmay be utilized to maintain a higher concentration of zinc chloride in the cellthan heretofore obtained; This higher concentration of zinc chloride materially increases the etliciency of the cellsin certain types of service,

but it is difficult to secure such concentration in factory practice.

Accordingly it is an object of the present invention to eliminateair bubbles within or adj acentfto the b-ibulous envelope and at the same time to do away with some of the difliculties incident to the use of a wrapping ofthread about the bibulous material. A further object is to eliminate the step of apply ing cereal paste either to the bobbin or to the i wrapper. lt'is a further object of the inventionto improve the service and shelf characteristics result, and moreover where'paper is used the wrapped bobbin has not been uniformly efli-- han a New Kinematic to,

of vthecell by the use of a higher V tienfef; zincchlcride in, effective relation with thpnaix nd in vo drth t ifi ltie in i s introduction which have been heretofore ennte eclw:

. Other objects invention will be made clear; the :iollowing detailed description, which'fis to, be read-1 71 h-1on1. w h; h a aempanyins ra a 111g, rr ie u fF g-ril l sec en l tio w a pl y a la-h 1 g isarempwt ve r a i ry ell re a e cqn rnt d in accordance 'vrith the'fpresfent invention.

In accordance with'the method of the present invention, the paper envelope or wrapper for the bobbin is wet with a solution of zinc chloride or of'zinc chloride-and ammonium chloride and then, while in the wet state, is

wrapped about the bobbin; Due to the partial gelatinization-of the cellulose of the paper, the wrapper, when wrapped about the bobbin and squeezed firmly against the same .trary greatly increases "the 'mechanical. strength of the bobbin, decreases dangerf internal short circuits and materially increases the service efiiciency of the cell. Y

Thin and? orous tissue papers of good quality have een found to be most suitable for wrapping bobbins." While the concentration of zinc chloride solution may be varied through a wide range, it ispreferred to use concentrations substantially. higher than those employed in the ordinary electrolyte solution. The following "results have been obtained with solutions of different concentrations: p 7 p I V v Service A. -Unwrapped bobbin (control) 100 B.-Wrapped; paperl wet with solution containing 100 parts of water to C.Wra'pped; paperfwet with solution containing partsof water to 80 'I parts of ZnC1 -s 7 Fig. 1 illustrates an assembled cell, wherein 1 indicates the zinc cup or anode containing a cathode 2 comprising thecarbon rod 4 and molded mass of depolarizing mix surrounding the same. The cathode is provided with a closely adherent wrapping 3 of paper impregnated with zinc chloride solution and is centrally positioned within the zinc cup by means of a serrated disk 5 of cardboard. The

space between the bobbin 2 and the zinc cup is filled with a gelatinized paste electrolyte 6. On top of the bobbin and paste is located a washer or disk 7 which serves to center the bobbin and to support a layer 8 of sealing wax or pitch.

I claim: I

1. A dry cell cathode having a self-sustain- I ing envelope impregnated with zinc chloride and cemented to the cathode with the reaction v product of zinc chloride on the envelope.

2. In the manufacture of a dry cell of the bag type, the steps of treating a sheet of cellulosic material with zinc chloride to gelatinize the former, and cementing thesheet to the as surface of the cathode by the adhesive action of the gelatinized cellulose. V

In testimony whereof, I affix my signature.

. GEORGE W. HEISE. 

